dom/mdsal-dom-inmemory-datastore/src/main/java/org/opendaylight/mdsal/dom/store/inmemory/InMemoryDOMStoreTreeChangePublisher.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.mdsal.dom.store.inmemory;
   9
  10 import static com.google.common.base.Preconditions.checkState;
  11
  12 import java.util.Collection;
  13 import java.util.Optional;
  14 import java.util.concurrent.ExecutorService;
  15 import org.eclipse.jdt.annotation.NonNull;
  16 import org.opendaylight.mdsal.dom.api.DOMDataTreeChangeListener;
  17 import org.opendaylight.mdsal.dom.spi.AbstractDOMDataTreeChangeListenerRegistration;
  18 import org.opendaylight.mdsal.dom.spi.store.AbstractDOMStoreTreeChangePublisher;
  19 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  20 import org.opendaylight.yangtools.util.concurrent.QueuedNotificationManager;
  21 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
  22 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerNode;
  23 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
  24 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
  25 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidates;
  26 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeSnapshot;
  27 import org.slf4j.Logger;
  28 import org.slf4j.LoggerFactory;
  29
  30 final class InMemoryDOMStoreTreeChangePublisher extends AbstractDOMStoreTreeChangePublisher {
  31     private static final Logger LOG = LoggerFactory.getLogger(InMemoryDOMStoreTreeChangePublisher.class);
  32
  33     private final QueuedNotificationManager<AbstractDOMDataTreeChangeListenerRegistration<?>, DataTreeCandidate>
  34         notificationManager;
  35
  36     InMemoryDOMStoreTreeChangePublisher(final ExecutorService listenerExecutor, final int maxQueueSize) {
  37         notificationManager = QueuedNotificationManager.create(listenerExecutor, (listener, notifications) -> {
  38             if (!listener.isClosed()) {
  39                 listener.getInstance().onDataTreeChanged(notifications);
  40             }
  41         }, maxQueueSize, "DataTreeChangeListenerQueueMgr");
  42     }
  43
  44     private InMemoryDOMStoreTreeChangePublisher(final QueuedNotificationManager<
  45             AbstractDOMDataTreeChangeListenerRegistration<?>, DataTreeCandidate> notificationManager) {
  46         this.notificationManager = notificationManager;
  47     }
  48
  49     QueuedNotificationManager<?, ?> getNotificationManager() {
  50         return notificationManager;
  51     }
  52
  53     @Override
  54     protected void notifyListener(final AbstractDOMDataTreeChangeListenerRegistration<?> registration,
  55             final Collection<DataTreeCandidate> changes) {
  56         LOG.debug("Enqueueing candidates {} for registration {}", changes, registration);
  57         notificationManager.submitNotifications(registration, changes);
  58     }
  59
  60     @Override
  61     protected synchronized void registrationRemoved(
  62             final AbstractDOMDataTreeChangeListenerRegistration<?> registration) {
  63         LOG.debug("Closing registration {}", registration);
  64
  65         // FIXME: remove the queue for this registration and make sure we clear it
  66     }
  67
  68     <L extends DOMDataTreeChangeListener> ListenerRegistration<L> registerTreeChangeListener(
  69             final YangInstanceIdentifier treeId, final L listener, final DataTreeSnapshot snapshot) {
  70         final AbstractDOMDataTreeChangeListenerRegistration<L> reg = registerTreeChangeListener(treeId, listener);
  71         final Optional<NormalizedNode<?, ?>> preExistingData = snapshot.readNode(YangInstanceIdentifier.empty());
  72         if (!preExistingData.isPresent()) {
  73             listener.onInitialData();
  74             return reg;
  75         }
  76
  77         final NormalizedNode<?, ?> data = preExistingData.get();
  78         if (treeId.isEmpty()) {
  79             checkState(data instanceof DataContainerNode, "Unexpected root node %s", data);
  80             if (((DataContainerNode) data).getValue().isEmpty()) {
  81                 // If we are listening on root of data tree we still get empty normalized node, root is always present,
  82                 // we should filter this out separately and notify it by 'onInitialData()' once.
  83                 // Otherwise, it is just a valid data node with empty value which also should be notified by
  84                 // "onDataTreeChanged(Collection<DataTreeCandidate>)".
  85                 listener.onInitialData();
  86                 return reg;
  87             }
  88         }
  89
  90         final DataTreeCandidate candidate = DataTreeCandidates.fromNormalizedNode(YangInstanceIdentifier.empty(), data);
  91         final InMemoryDOMStoreTreeChangePublisher publisher = new InMemoryDOMStoreTreeChangePublisher(
  92             notificationManager);
  93         publisher.registerTreeChangeListener(treeId, listener);
  94         if (!publisher.publishChange(candidate)) {
  95             // There is no data in the conceptual data tree then
  96             // notify with 'onInitialData()'.
  97             listener.onInitialData();
  98         }
  99
 100         return reg;
 101     }
 102
 103     synchronized boolean publishChange(final @NonNull DataTreeCandidate candidate) {
 104         // Runs synchronized with registrationRemoved()
 105         return processCandidateTree(candidate);
 106     }
 107 }